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TNG photometry of the open cluster NGC 6939

G. Andreuzzi·A. Bragaglia·M. Tosi·G. Marconi
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Abstract

We present CCD UBVI photometry of the intermediate age open cluster NGC 6939 for three TNG-DOLORES fields. The fields A and B cover the center of the cluster; the third one is located about 30 arcmin away, and is used for field stars decontamination. The V-I, B-V and U-B color-magnitude diagrams (CMDs), obtained joining very different exposures show: i) a Main Sequence (MS) extending down to V = 24, much deeper (~ 5 magnitudes) than any previous study; ii) a clearly defined Turn Off (TO) and iii) a well populated Red Giant Clump (RC) at about V = 13.

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G. Andreuzzi, A. Bragaglia, M. Tosi, G. Marconi. 2003-05-29. TNG photometry of the open cluster NGC 6939. https://arxiv.org/abs/astro-ph/0305561

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